1. Field of the Invention
This invention relates to a connector arrangement for an EL lighting element, in which large area electrodes on the EL lighting element directly engage a specially designed connection member to facilitate electrical connection of the lighting element to the metal plug, thereby eliminating the need for conventional claw type or glue-type terminal arrangements, thereby simplifying assembly of the lighting element while reducing the risk of short circuits, electric shock, and sparking which could present a fire hazard. The invention also relates to an electro-luminescent lighting element for use in such a connector arrangement, and to a night light in which the connector arrangement is used.
2. Discussion of Related Art
The present invention utilizes the connector principles disclosed in parent application Ser. No. 08/383,404 now U.S. Pat. No. 5,667,394, but explicitly extends the concept to a variety of different types of electro-luminescent lighting element. Examples of EL lighting elements which may be used with the connector arrangement disclosed in the parent application and also disclosed herein are the electro-luminescent panels disclosed in U.S. Pat. No. 5,572,817, and in copending U.S. patent application Ser. Nos. 08/729,408 (now U.S. Pat. No. 5,752,337), 08/734,872 (now U.S. Pat. No. 5,883,508), and 08/746,706 (now U.S. Pat. No. 5,734,366), each of which is incorporated by reference herein, as well as the three-dimensional electro-luminescent tube arrangement disclosed in U.S. patent application Ser. No. 08/758,393 (pending), which is also incorporated by reference herein. The connector arrangement disclosed herein may also be used with the optical device disclosed in U.S. patent application Ser. No. 08/841,624 (pending), also incorporated herein by reference, which is a continuation of U.S. patent application Ser. No. 08/489,160 (abandoned).
The description of the invention contained herein is the same as that of the parent application, except that it is clarified that the connector can be used with a number of different lighting elements, that the lighting element itself is not limited to the particular "wire" and conductive member illustrated in the description of the preferred embodiment of the invention, and in that a detailed description of a night light utilizing the principles of the invention has been added.
Basically, the invention simplifies assembly of the connector by utilizing non-penetrative contact between wide area electrodes on the electro-luminescent element and a resilient conductive member. FIGS. 4, 5A, and 5B of parent U.S. patent application Ser. No. 08/383,404, now U.S. Pat. No. 5,676,394 show one example of a connector utilizing these principles, and FIGS. 1B-1D, 3A, and 3B of the parent application give one example of an electro-luminescent element, referred to in the parent application as an EL strip, which may be used in the connector utilizing the principles of the invention. However, while the lighting element shown in FIGS. 1B-1D, 3A, and 3B of the parent application is especially suitable for use with the connector of FIGS. 4, 5A, and 5B of the parent application, as well as the arrangement illustrated in the present application, it will be appreciated by those skilled in the art that any electro-luminescent lighting element with appropriately configured electrodes, including those described in the above cited U.S. Pat. Nos. 5,752,337, 5,883,508, and 5,794,336 and application Ser. No. 08/758,393.
The problems with prior electro-luminescent elements per se is described in detail in the parent application, and need not be repeated herein. Instead, the following discussion relates to the particular application of a night light, which particular benefits from the principles disclosed in the parent application.
In particular, as shown in FIGS. 1 and 2, the conventional means for electrically connecting an electro-luminescent element 1 to a plug is use claw-type metal terminals 2, the teeth 3 of which are designed to penetrate the surface of electrodes or contacts on the electro-luminescent element. In the case of a night light, extensions 4 of these terminals are then connected to the prongs 5 extending through the housing 6 of a plug assembly arranged to be inserted into a wall outlet.
FIG. 3 shows an arrangement similar to that shown in FIGS. 1 and 2, with claw type terminals 7 extending from an electro-luminescent panel 8 attached to prongs 9 secured to the panel by double-sided tape 10 for use in a housing having a rear section 11, and a front section 12 having a window 13 through which the electro-luminescent panel 8 is visible to form the night light.
The problem with the use of claw type terminals, which are designed to push through the multiple layers of the electro-luminescent panel, is that the teeth on the terminals can easily cause damage to the panels during assembly, resulting in a high percentage of defective assemblies, and presenting a serious hazard of electrical shock. This is especially significant in the case of night lights, which are often placed in places where young children may have access to them.
This problem is solved in the parent application by establishing the electrical connection using a resilient conductive member to provide a self-biasing connection between connection wires and the large area terminals on the electro-luminescent element illustrated in the parent application. However, the concept of using a resilient or self-biased arrangement is not limited to the particular conductive member and wire arrangement described in the parent application, but rather can be applied in a wide variety of contexts to a wide variety of different types of electro-luminescent element, and in the case of a night light greatly reduces the above-noted safety problem presented by claw type terminals, while actually simplifying assembly because the force necessary to cause penetration is not required.